Graph G is obtained by adding vertex s to K3,4 and making s adjacent to every vertex of K3,4. The minimum number of colours required to edge-colour G is _______.

Correct Answer:

7

Solution:

Edge Coloring: Edge coloring of a graph means assigning 'color' to the edges of a graph such that no two incident edges on the same vertex have the same color.

According to the question, graph G is obtained by adding vertex s to K3,4 such that s is adjacent to every vertex of K3,4.

After adding vertex s to K3,4.
Vertex s has the highest degree in G (s is connected to the 7 edges). So, the minimum number of colors required to egde-color G is 7.